Automatically-operating oxidator for attachment to furnace doors for abating smoke



Nov. 9 1926. 7 1,506,374

J. A. MILLER AUTOMATICALLY OPERATING OXID ATOR FOR ATTACHMENT T0 FURNACEDOGRS FOR ABATING SMOKE Original Filed Oct. 9, 1922 2 Sheets-Sheet 1 GHOLY! c u Nov. 9, 1926. 1 EJ506374 J. J. A. MILLEQ I AUTOMATICALLYOPERATING OXIDATOR FOR ATTACHMENT 'IO FURNACE DOORS FOR ABATING SMOKEOriginal File 00L 9, 1922 2 Sheets-Sheet .2

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Patented Nov. 9, 1926.

JO :1" 3'. A. MILLER, GE DENVER, COLORADO, ASSIGNOR TO THE AUTOMATICFURNACE i 318E011 AND MANUFACTURING COMPANY, OF DENVER, COLORADO, ACORPORA- ZIZOH OF COLORADO.

AUTOMATI ALLYOPERATING OXIDATOR FOR ATTACHMENT .TO FURNACE DOORS FOR 7if ABA'IING SMOKE.

Application filed Gctober 9, 1922', Serial No. 593,475. Renewed March31, 1926.

tachment to furnace doors for abating smoke.

The object of the invention is to provide an attachment for the doors offurnaces, comprising a shutter controlled air heater and automaticallyoperating mechanism for operating the shutters, by which the shuttersare opened simultaneously with the closing of the door to permit air toenter the furnace through the air heater, means being connected with theshutter operating mechanism for gradually closing theshutters within apredetermined period.

Further, to provide in connection with the shutter operating mechanismof oxidators or smoke abating attachments of this character. a gravityoperated oil controlled piston, which is raised in an oil cylinder bysaid shutter operating mechanism simultaneously with the opening of theshutters, the length f time required for the descent of said piston, andconsequently for the closing of the shutters, being determined by anadjustable valve in said piston, which permits the free upward stroke ofthe piston through the oil, but retards its descent, saidshutterspermitting a regulated supply of air through the heater to thefurnace for a given period after the coaling operation, the said airbeing discharged over the coal bed, by which it is mixed with hecombustible gases and floating particles of carbon and tar,thus causingcomplete combustion of these particles and the consequent elimination ofsmoke.

These objects are accomplished by the mechanism illustrated in theaccompanying drawings, in which: V

Figure 1 is'a front view of a furnace door equipped with the improveddevice;

Fig. 2 is a top view, partly in section, of Figure 1, the cap'of thehousing being removed;

Fig. 3 is an enlarged vertical sectional view of the housing on the line3-3 of Figure 1;

Fig. t is an enlarged sectional view on the line l l of Figure 1;

Fig. 5 is a plan view of a portion of the door provided with theimproved device, the door being partly open, and

Fig is a front View of the air pre-heater. Visible furnace smoke can beabated only by effecting complete combustion in the fur-' dation of allcombustible matter, and theintimate mixing of the air with thecombustible gases and the floating particles of carbon and tar, To bringabout this result, air in large quantities should be admitted over thefire immediately after coaling, and this quantity should be graduallyreduced as the distillation of the volatile coin-bustible nearscompletion. 1

Theimproved furnace door attachment is adapted to meet theserequirements, by

means of a combination of elements, which are arranged and constructedas follows:

Referring to the accompanying drawings:

The numeral 1 indicates the front wall of an ordinary furnace,- and 2the fire door Which is hinged to the furnace in the usual manner, andto-which the present invention is secured.

The door is provided with a circular opening 8, which is about teninches in diameter, and an improved air pre-heater is bolted to the backof the door to registerwith the opening 3. Tlie-pre hea'ter comprises aplu rality of spaced rectangular outwardly flaring metal frames t,arranged one within the other, and connected to form an integral st'ucture by radial webs 5, which extend between and connect eachtwofrai'nes as clearly shown in Figure 6.

The frames increase in depth progressively from the outer frame, whichis about five inches in depth, to the innermost frame 6, which ispractically a rectangular tube. Apertured lugs 7 are formed on thesmaller end of the outerframe 4: and bolts 8 are passed through theselugs and through the door, and through lugs 9 on a rectangular frame 10on the front side of the door, thus securing both-the pre-heater and theframe 10 to opposite sides of the door.

The outer frame of the pre-heater is about five inches in depth, and theremaining frames increase in depth progressively toward the innermostframe or tube 6, which is the deepest. When the furnace door is closed,the pro-heater extends in, over and above the coal bed of the furnaceand is thus heated to a high degree of temperature, so

u this a --;phcric airpassing through itinto the furnace is hi y heatedin passing th. ugh the said pre-heater, as will be understood.

The width of the frame 10, from side to ide'is the same as the diameterof the hole in the door. This frame is provided with a series ofoverlapping shutters 11 in the form of thin metal blades havingapertured lugs 12 on their oposite ends and centrally of their widths,to receive pivot pins 13, which are mounted in two opposite sides of theframe.

The central shutter has a lug 12 on one end only, and upon the opositeend of this shutter is riveted the bifurcated end of a shaft 1 1, whichextends through the adjacent side of the frame 10, and through theadjacent side of a housing 15, which is secured to the frame 10 and tothe front side of the furnace door, as will later appear. The shutters11 are connected to turn in unison by a flat connecting rod 16, whichlies between pairs of ears 17 on the shutters, and is pivotallyconnected to each pair of ears. hen the central shutter is turned by theshaft 1 1; in a manner to be presently described, the other shutters arealso turned through their connection with the rod 16.

The housing 15 is divided into two chambers 18 and 19, by a partition20, which extends far enough above the bottom of the housing to providea bearing for the free end portion of the shaft l l, which passesthrough it. The housing is provided on the side next the furnace doorand on the side next the frame 10, with bosses 21, which define a spacebetween the housing and the door and between the housing and the frame10, and bolts 22 pass through the bosses and the door on one side of thehousing, and through the bosses and the frame 10 on another side of thehousing, by which the housing is firmly secured to the frame 10 and tothe door. The bosses prevent the housing from contact with both the doorand frame, and permit the circulation of air between these parts, thuskeeping the housing from becoming unduly heated.

An oil holding cylinder 23 depends from r the bottom of the chamber 18and opens into the said chamber at its upper end. A. hollow piston 24 ismounted in this cylinder, the lower end'wall of which is provided with acircular axial hole 25, and its upper end is formed with four radialarms or spokes 26, to which are integrally connected an upwardlyprojecting axial hub 27, in which is inserted the reduced portion of apiston rod 28, in the form of a rack bar, having annular teeth 29, thebar 28 being held in the hub by a pin 30, which passes through the hubmo em and through a groove in the said reduced portion of the rack bar,or piston rod, as it will hereafter be termed.

The piston rod has an axial hole 31 er:- tending through the same, thelower portion of which is threaded, and a stem 32- is screwed into thisthreaded portion of the hole and extends through the hole 25 in thebottom of the piston.

The portion of the stem projecting below the bottom of the piston isreduced in diameter, as shown at 33, to form a shoulder at the junctionof the two diameters, and a disk valve 85, having an axial hole, isslipped on the reduced portion 33 and is normally held against theshoulder 3% by a spiral coil spring 36, which surrounds the reducedportion of the stem and is held in place by a pin 37, which passesthrough the reduced portion and engages the bottom coil of the spring.The housing is closed by a cap 38 having a threaded hole 89 in line withthe hole 31 in the piston rod, which is normally closed by a screw 10.The upper end of the stem 32 is formed with a crew driver slot, and bypassing a screw driver down through the hole 39 in the cap and into thehole 31 in the piston rod, the valve stem 32 may be adjusted to vary thedistance be tween the disk valve '35, and the end wall of 1" the piston,by which the period required for the piston to make its downward strokethrough the oil in the cylinder may be lengthened or shortened to meetrequirements, for a reason to be later set forth, and the spring 36permits the disk valve to move down or away from the opening 25 underthe pressure of the oil when the valve is raised, so as to permit freepassage of the oil through the piston.

The shaft 14 has rigidly mounted thereon a segment gear 41, which mesheswith the toothed piston rod 28, and when the shaft is turned to open theshutters 11, in a manner to be presently described, the gear 1-1 acts toraise the piston, and when the piston descends, the shaft 14 is therebyturned to close the shutters.

A boss 42 is formed on the outer face of the front of the housing,centrally of the width of the chamber 19, and near the upper end of thesame, and this boss is formed with a threaded aperture which extendsthrough the said front wall and into which is screwed the reducedthreaded portion of El the housing, and through a hole 48 in the l inneoaeva door and its forward end is of conical form and when the door isclosed bears against the front wall of the furnace and close to the sidemargin of the coal opening A therein, which is normally closed by thesaid door. A pin 49 extends through the bar l6, about midway of itslength, and a coil spring 50 surrounds the bar and the hub portion l ofthe knob 48 and is held under. compression between the pin l9 and theend of the threaded portion of the knob, when the door is closed.

A cylindrical slide block 51, having annular gear teeth 52, is mountedon the bar 46, and this block meshes with a segment gear 53, which isrigidly secured upon the shaft 14, the said shaft being below the bar asshown by Fig. 3.

When the piston is at the limit of its downward stroke, the gear 53 hasmoved the block 51 rearward on the bar d6, until its rear end engagesthe pin 49, and the parts remain in these positions as long as the dooris closed. V

The right hand marginal edge of the coal opening A in the furnace wall,is formed with a recess 54, having an inclined bottom which slopes upfrom the edge'of the open ing and this recess lies in thepath of theconical end of the slide bar 4-6. When the door is closed, the saidconical: end of the bar engages the incline 54;, by which the bar isslid back to the position shown in Fi e 3 and bears against the walljust beyond the highest point of the incline.

in operation, when the furnace door is opened, as for coalingytheconical end of the slide bar 46 is released from engagement by thefurnace wall, and the said'bar is projected by the spring 50, whichbears against the pin &9 insaid bar. The toothed slide bloclr 51 alsoengages the pin at: on the opposite side from the spring 50, and therefore the said slide block is moved forward with the bar until it engagesthe rear wall of the housing, thereby turning the small segment gear 58,by which the shaft 14 is also turned to open the shutters 11 to permitair to enter the furnace through the preheater, while the segment gearll, which meshes with the toothed piston rod 28, raises the piston 24:to the limit of its upward movement. After the coaling, the furnace dooris closed thereby bringing the conical end of the slide bar 4-6 intoengagement with the incline 54, as previouslydescribed, by which the baris moved back to the position shown in Fig. 3 thereby compressing thespring 50. c

The slide block 51, however, is not carried back with the bar, but whenthe bar moves back, instantly the pin l9 releases the slide block whichis then gradually slid back on the bar by the descent of the pistonwhose toothed rod 28 turns the segment gear ll, shaft 1 and segment gear53, which gear slides the bloclr 51 baelr until it engages the pin 49.The turning of the shaft i l graduallycloses the shutters 1i and thetime occupied by the piston in descending from its highest to its lowestposition is determined by the adjustment of the valve with respect tothe bottom of the piston. The bottom of the cylinder 23 is provided witha drain hole which is normally closet by a screw 55. i

iiaving described my invention, what I claim as new and desire to secureby Letters Patent, is:

1. In a device of the character described, the combination with afurnace door, a prehoater thereon and shutters for permitting air toenter the furnace through the preheater, of a spring-actuated bar whichis projected when the door is opened, mechanism including a slidablemember operated by said bar to open the shutters simultaneously with theopening of the door, means to reverse the movement of the bar when thedoor is closed, thereby releasing the Slit able member, andmeans toreversethmovement of the mechanism to close the shutters.

2. In a device of the character described, the combination with afurnace door, an air heater thereon and shutters for permitting air toenter the furnace through the heater, of a gravity device, mechanismincluding a slidable member connected with the gravity device and withsaid shutters, a sprin actuated slide bar which isprojectedsimultaneously with the opening of the door, to operate themechanism whereby the shutters are opened and thegravity device raised,and means to reverse the slide bar whe' the door is closed therebyreleasing the slidable member, whereby the mechanism is hen actuated bythe gravity device to gradually close the shutters. V p

3. in a device of the character described, the combination with afurnace door, an air heater thereon, and connected pivoted shutters'foradmitting air to the nace through said heater, of a gravity-a idoil-controlled piston, gearing connected with the piston and with one ofsaid shutters, a spring-actuated slide bar which isprojectedsimultaneously with the opening of the door, to operate the gearing,whereby the shutters are opened and the piston 1' Ted, and means wherebythe i when the door closed thereby relate the gearing which is thenactuated ti e gravity-actuated piston to gradually close .the shutters.

l. In a device of he character described, the combination with a furnacedoor, an air heater thereon and connected pivoted shutters for admittingair to the furnace through the Theater, of a gravity device, mechanismconnected with the gravity del in O mu

vice and with one of said shutters, a spring actuated slide bar which isprojected simultaneously with the opening, means connected with themechanism and movable with the bar when it is projected, whereby themechanism is operated to open the shutters and raise the said gravitydevice, and means whereby the slide bar is reversed when the door isclosed thereby releasing the slidebar-operated means and permitting thegravity device to reverse the said mechanism and gradually close theshutters.

In a device of the character described, the combnation with a furnacedoor, an air heater thereon and connected pivoted shutters for admittingair to the furnace throughthe heater, of an oil-controlled, gravityactuated valved piston, mechanism connected with one of the shutters andwith the piston, a spring-actuated slide bar which is projectedsimultaneously with the opening of the door, a block slidable on the barand moved with the bar vhen the same is projected, said block being:connected with the mechanism whereby the same is operated to open theshutters and raise the piston; means whereby the bar reversed when thedoor is closed, thereby releasing the block and permitting the piston toreverse the mechanism whereby the shutters are gradually closed, and theslide block moved to its former position on the slide bar. 7

6. In a device of the character described, he combination with a furnacedoor, an air heater thereon, and connected, pivoted shutters foradmitting air to the furnace through said heater; of a-housing on saiddoor having a depending oil holding cylind r, a valved piston in saidcylinder having a toothed piston rod, a shaft mounted in the housingwhich is connected at one end with the axial portion of one of theshutters, a gear on the shaft in mesh with the toothed piston rod, asring-actuated bar mounted in the housing which is pro-- jected beyondthe rear wall of the housing simultaneously with the opening of thedoor, a block slidably mounted on the bar, having annular teeth andmovable with the bar when the same is projected, a gear on the shaft inmesh with the toothed block, whereby when the bar is projected the shaftis turned to open the shutters and lift the piston, and an incline onthe furnace wall which is engaged by the end of said bar 7 when the dooris closed, whereby the bar is retracted and the slide block releasedpermitting the piston to descend to gradually close the shutters andrestore the a housing secured to the door and spaced therefrom, having adepending Oll holding cylinder, a piston in said cylinder having anadjustable valve and a toothed piston rod, a shaft mounted in saidhousing which is secured at one end to the axial portion of one of saidshutters, agear thereon in mesh with the toothed piston rod, a barslidably mounted in the housing and extending through the rear wall ofthe housing and through the door to engage said furnace wall, anabutment on the bar, a spring surrounding said bar and under compressionbetween the abutment and the front wall of the housing for projectingsaid bar when the door is opened, a block slidably mounted on the bar,having annular teeth, and in normal engagement with said abutment, and agear on said shaft in mesh with said toothed block whereby when the baris projected, the shaft is turned to open the shutte ano raise thepiston, and an incline on the furnace wall which is engaged by the endof the bar when the door is closed whereby the bar is retracted and theslide block released permitting the piston to gradually descend andclose the shutters restore the slide block to its former position on theslide bar.

8. In a device of the character described, the combination with afurnace door, an air heater thereon, connector pivotally mountedshutters on the door for admitting air to the furnace through theheater, and a shaft connected to one of said slmtters for turning thesame; of a housing secured to the door is opened, a slide blocl: mountedon the bar, havin annular teeth. an abut mentpin in said bar fordefining the rearward movement of the slide block, and for carrying theslide block forward to engage the rear wall of the housino' when the baris projected, a gear on said shaft in mesh. with the slide block,whereby the shaft is turned to open the shutters when the bar isprojected, an incline on the furnace wall for engaging the bar toretract the same when the door is closed, whereby the slide block isreleased, and a gravity device connected with the shaft for graduallyclosing the shutters.

9. In a device of the character described, the combination with afurnace door, an air heater on the inner side of the door, a frame HillllU

on the front side or" the door, shutters pivotallv mounted in said frameand connected to turn in unison, and a shaft connectec to the axialportion of one of said shutte "s; of spring ogerated slidahle means andmechanism connected therewith for opening the shutters simultaneouslywith the opening oi the door ant an oil-controlled gravity deviceconnected with the mechanism for gradually closing the shutters afterthe door is closed.

10. in a device of the character described the combination with a serieso1 connected pivoted sj-1hntters and mechanism for opening saidshutters; of means for closing the shutters comprising a grevityectnatedoilcontrolled hollow piston connected with said mechanism, having anopen upper end provided with an axial huh having a threaded bore, and alower end wall provided with an axial hole, stein threaded to said boreand xtending down through said axial hole, the portion oi the sternbelow the bottom wall of the piston being reduced to form a shoulder, adisk valve on the reduced portion of the stem, :1 pin in said reducedportion, and a spiral. coil. spring interposed between the Jill and thedisk valve to hold the valve against said shoulder, said disk valve beinof greater diameter than the hole in the bottom of the valve, said valvebeing adjusted with. respect to the said hole by turn ing said stein inthe said hub.

In testimony whereof I ati'iX my signature.

JOHN J. A. lvillilil lll.

